sizing power heads and pumps

[reef tank 2.0]

question....when determining amount of flow (powerhead) i see the typical factor is 20-50x water volume. for the return pump size, it's 5-10x water volume.

is that water volume the DT volume, or the total volume of display tank and sump combined? just double checking.

 

[DCR]

It is not that exact but generally the nominal volume of the display tank is what people are referring to when using these factors.